JP6554221B2 - Magnetic core - Google Patents
Magnetic core Download PDFInfo
- Publication number
- JP6554221B2 JP6554221B2 JP2018187447A JP2018187447A JP6554221B2 JP 6554221 B2 JP6554221 B2 JP 6554221B2 JP 2018187447 A JP2018187447 A JP 2018187447A JP 2018187447 A JP2018187447 A JP 2018187447A JP 6554221 B2 JP6554221 B2 JP 6554221B2
- Authority
- JP
- Japan
- Prior art keywords
- iron
- epoxy resin
- powder
- magnetic core
- based soft
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Soft Magnetic Materials (AREA)
Description
本発明は磁性コアおよびその製造方法に関し、特に高周波焼入装置の加熱コイル部に取り付けられる鉄系軟質磁性コアおよびその製造方法に関する。 The present invention relates to a magnetic core and a method of manufacturing the same, and more particularly to an iron-based soft magnetic core attached to a heating coil portion of an induction hardening apparatus and a method of manufacturing the same.
磁性コアは、コイルの背面に取り付けてワークに磁力線を集中させパワーを増強し誘導加熱を促進させる効果や、反対にコイルの前面に取り付けて磁力線を遮蔽（シールド）し焼入れ不要部位の加熱を防ぐ効果があり、高周波焼入装置の加熱コイルには欠かせない部品となっている。
例えば、高周波焼入するワークの形状が複雑で焼入深さを調整する必要がある場合は、取り付けるコアの形状、サイズ、数量、方向、位置などを変更することにより誘導加熱の状態を変化させることができ、ワークの焼入深さを制御することが可能となる。このコア材料には、（１）周波数特性が良好なこと、すなわち周波数の変化に伴うインダクタンスの変化が少ないこと、（２）飽和磁束密度が高いこと、（３）比透磁率が高いこと、（４）鉄損が小さいこと、などの磁気特性が必要となる。
また、多様なワークの形状に対応するため、コア部品も多品種少量生産となることが多く、１つ１つ切削対応にて生産されることが多い。このため、強度が高く切削性に富んだ材料が求められている。
The magnetic core can be attached to the back of the coil to concentrate magnetic lines of force on the workpiece to increase power and promote induction heating, and conversely, it can be attached to the front of the coil to shield the magnetic lines and prevent heating of parts that do not require quenching. It is effective and has become an indispensable part for the heating coil of induction hardening equipment.
For example, if the shape of the workpiece to be induction hardened is complicated and it is necessary to adjust the hardening depth, change the shape of induction heating by changing the shape, size, number, direction, position, etc. of the core to be attached It is possible to control the hardening depth of the work. The core material has (1) good frequency characteristics, that is, small change in inductance due to change in frequency, (2) high saturation magnetic flux density, and (3) high relative permeability ( 4) Magnetic properties such as low iron loss are required.
Moreover, in order to cope with various workpiece shapes, core parts are often produced in a variety of small quantities, and are often produced by cutting one by one. Therefore, materials having high strength and high machinability are required.
粉末冶金法により製造される磁性コアは、原料ロスが少なく量産性に優れるため、高周波焼入装置の加熱コイルに用いられる磁性コアとして多用されている。
従来、高周波焼入コイル用磁性コアとしては、例えば、鉄粉をフッ素樹脂で固着したフラクストロールＡ（Ｆｌｕｘｔｒｏｌ社製商品名）や、センダスト粉をフェノール樹脂で固着したポリアイアン（ＮＥＣトーキン（株）社製商品名）などが使用されているが、それらの材料強度は比較的低く、薄肉切削時の割れ発生や、コイル取付け時の破損等の問題があった。
Magnetic cores manufactured by powder metallurgy are frequently used as magnetic cores used in heating coils of induction hardening devices because they have low material loss and excellent mass productivity.
Conventionally, as a magnetic core for induction hardening coils, for example, fluxolol A (trade name of Fluxtrol Co., Ltd.) in which iron powder is fixed by a fluorine resin, or polyiron (NEC TOKIN Co., Ltd.) in which Sendust powder is fixed by phenol resin. However, the strength of these materials is relatively low, and there have been problems such as cracking during thin wall cutting and damage during coil mounting.
一方、電動機またはリアクトルを対象用途とした磁性コアとして、純鉄粉の表面に予め絶縁被膜を有す磁性粉末とシリコン樹脂粉末を混合して、所定の温度雰囲気下で樹脂粉末をゲル化して加圧成形（温間成形）する圧粉磁心の製造方法が知られている（特許文献１）。
また、還元鉄粉末に該粉末の多孔度を余り減じない程度に熱硬化性エポキシを混和被覆した後に、加圧成形、硬化および含油の工程による鉄系含油軸受の製造方法が知られている（特許文献２）。
On the other hand, as a magnetic core intended for electric motors or reactors, magnetic powder having an insulating coating on the surface of pure iron powder and silicon resin powder are mixed, and the resin powder is gelled under a predetermined temperature atmosphere. DESCRIPTION OF RELATED ART The manufacturing method of the powder magnetic core which pressure-molds (warm shaping | molding) is known (patent document 1).
In addition, a method for producing an iron-based oil-impregnated bearing by a process of pressure molding, curing and oil impregnation after reducing iron powder is mixed and coated with a thermosetting epoxy to such an extent that the porosity of the powder is not significantly reduced ( Patent Document 2).
特許文献１に記載の方法では、純鉄粉の表面に予め絶縁被膜を有す高価な原料鉄粉を使用する必要があり、さらに生産性の落ちる温間成形を用いて樹脂粉末をゲル化して加圧成形するため、原料コスト上昇と生産性の低下および設備費用がかかるという問題がある。
特許文献２に記載の鉄系含油軸受の場合、還元鉄粉末への絶縁が十分でなく、磁性コアとしての磁気特性を得ることが困難である。
さらに、磁性コアを高周波焼入コイル用として使用する場合、従来使用されている磁性コアは、その材料強度が低く、薄肉切削時の割れ発生や、コイル取付け時の破損等が生じるという問題がある。
In the method described in Patent Document 1, it is necessary to use an expensive raw iron powder having an insulating coating on the surface of pure iron powder in advance, and further, the resin powder is gelled by using warm molding with low productivity. There is a problem that the raw material cost is increased, the productivity is lowered, and the equipment cost is required because the pressure molding is performed.
In the case of the iron-based oil-impregnated bearing described in Patent Document 2, insulation to the reduced iron powder is not sufficient, and it is difficult to obtain magnetic characteristics as a magnetic core.
Furthermore, when the magnetic core is used for induction hardening coils, the conventionally used magnetic cores have problems such as low material strength, cracking during thin wall cutting, breakage during coil attachment, etc. .
本発明はこのような問題に対処するためになされたものであり、原料コストを上昇させることなく生産性を向上させ、磁性コア、特に高周波焼入装置の加熱コイル部等に取り付けられる軟質磁性コアに必要とされる磁気特性および機械特性を有する磁性コアおよびその製造方法の提供を目的とする。 The present invention has been made to address such problems, and improves productivity without raising the cost of raw materials, and a soft magnetic core attached to a magnetic core, particularly to a heating coil portion of an induction hardening apparatus, etc. It is an object of the present invention to provide a magnetic core having the required magnetic and mechanical properties and a method of manufacturing the same.
本発明の磁性コアは、樹脂被膜が粒子表面に形成された鉄系軟磁性体粉末を圧縮成形後に熱硬化させて製造され、上記樹脂被膜が潜在性硬化剤を含むエポキシ樹脂の軟化温度以上、熱硬化開始温度未満の温度で乾式混合することにより形成される未硬化樹脂被膜であり、上記圧縮成形が金型を用いる圧縮成形体の製造であり、上記熱硬化が上記潜在性硬化剤を含むエポキシ樹脂の熱硬化開始温度以上の温度で熱硬化させることを特徴とする。
上記鉄系軟磁性体粉末が還元鉄粉末であることを特徴とする。また、上記鉄系軟磁性体粉末は、タイラー篩番号で８０メッシュ（以下、単に８０メッシュという）を通過し、同３２５メッシュを通過しない粒子であることを特徴とする。
エポキシ樹脂に含まれる潜在性硬化剤がジシアンジアミドであり、この潜在性硬化剤を含むエポキシ樹脂の軟化温度が１００〜１２０℃であることを特徴とする。
また、上記鉄系軟磁性体粉末と潜在性硬化剤を含むエポキシ樹脂との合計量に対して、上記鉄系軟磁性体粉末が９５〜９９質量％、上記潜在性硬化剤を含むエポキシ樹脂が１〜５質量％配合されていることを特徴とする。
本発明の磁性コアは高周波焼入コイルに使用される磁性コアであることを特徴とする。
The magnetic core of the present invention is manufactured by thermosetting an iron-based soft magnetic powder having a resin coating formed on the particle surface after compression molding, and the resin coating is above the softening temperature of an epoxy resin containing a latent curing agent, An uncured resin film formed by dry mixing at a temperature lower than the heat curing start temperature, wherein the compression molding is the production of a compression molded article using a mold, and the heat curing includes the latent curing agent It is characterized in that it is thermally cured at a temperature higher than the thermosetting temperature of the epoxy resin.
The iron-based soft magnetic powder is a reduced iron powder. The iron-based soft magnetic powder is characterized in that it is a particle which passes 80 mesh (hereinafter referred to simply as 80 mesh) and does not pass 325 mesh in Tyler sieve number.
The latent curing agent contained in the epoxy resin is dicyandiamide, and the softening temperature of the epoxy resin containing the latent curing agent is 100 to 120 ° C.
Moreover, the epoxy resin containing 95 to 99% by mass of the iron-based soft magnetic powder and the latent curing agent with respect to the total amount of the iron-based soft magnetic powder and the epoxy resin containing the latent curing agent It is characterized in that 1 to 5% by mass is blended.
The magnetic core of the present invention is a magnetic core used for an induction-hardened coil.
上記本発明に係る磁性コアの製造方法は、上記鉄系軟磁性体粉末と上記エポキシ樹脂とを該エポキシ樹脂の軟化温度以上、熱硬化開始温度未満の温度で乾式混合する混合工程と、上記混合工程により生成した凝集ケーキを室温で粉砕して複合磁性粉末を得る粉砕工程と、上記複合磁性粉末を金型を用いて圧縮成形体とする圧縮成形工程と、上記エポキシ樹脂の熱硬化開始温度以上の温度で上記圧縮成形体を熱硬化させる硬化工程を含むことを特徴とする。特に上記圧縮成形工程が２００〜５００ＭＰａの成形圧力で成形されることを特徴とする。また、上記硬化工程が硬化温度１７０〜１９０℃で硬化されることを特徴とする。また、上記硬化工程が窒素雰囲気中で硬化されることを特徴とする。 The method for producing a magnetic core according to the present invention includes a mixing step in which the iron-based soft magnetic powder and the epoxy resin are dry-mixed at a temperature not lower than a softening temperature of the epoxy resin and lower than a thermosetting start temperature, and the mixing. A process of pulverizing the agglomerated cake formed by the process at room temperature to obtain a composite magnetic powder, a compression molding process of forming the composite magnetic powder into a compression molded body using a die, and a temperature above the thermosetting start temperature of the epoxy resin And curing the compression-molded product at a temperature of In particular, the compression molding process is characterized in that it is molded at a molding pressure of 200 to 500 MPa. Moreover, the said hardening process is characterized by hardening at 170-190 degreeC of hardening temperature. Further, the curing step is characterized in that it is cured in a nitrogen atmosphere.
本発明の磁性コアは、潜在性硬化剤を含むエポキシ樹脂の未硬化樹脂被膜が粒子表面に形成された鉄系軟磁性体粉末を圧縮成形後に熱硬化させて製造される磁性コアであるので、鉄系軟磁性体粉末と樹脂粉末とを単純混合して得られる磁性コアに比較して、比重の異なる鉄粉と樹脂粉末の偏析を低減し、圧縮成形時の圧縮性を向上させることができ、その結果、磁性コアの密度を向上させることができる。
また、鉄系軟磁性体粉末表面に形成されたエポキシ樹脂の絶縁被膜により鉄粉の素地が接触する頻度を低減し、磁気特性となる周波数特性を向上させることができる。
さらに鉄系軟磁性体粉の表面に形成されたエポキシ樹脂の熱硬化により材料強度向上に寄与し、圧環強度などの磁性コアの機械的強度を大幅に向上させることができる。また、窒素雰囲気中における硬化処理により酸化を低減し、飽和磁束密度や比透磁率などの磁気特性の低減を抑制する。
本発明の磁性コアは、粉末冶金法によるニアネットシェイプによって材料歩留り向上、工数削減、生産性向上およびコスト低減が実現でき、高周波焼入コイルに好ましく使用できる。
Since the magnetic core of the present invention is a magnetic core produced by thermosetting an iron-based soft magnetic powder having an uncured resin film of an epoxy resin containing a latent curing agent formed on the particle surface, after compression molding, Compared with a magnetic core obtained by simply mixing iron-based soft magnetic material powder and resin powder, segregation of iron powder and resin powder having different specific gravities can be reduced, and compressibility at the time of compression molding can be improved. As a result, the density of the magnetic core can be improved.
In addition, the frequency of contact of the iron powder base can be reduced by the insulating coating of the epoxy resin formed on the surface of the iron-based soft magnetic material powder, and the frequency characteristics as the magnetic property can be improved.
Furthermore, the thermosetting of the epoxy resin formed on the surface of the iron-based soft magnetic material powder contributes to the improvement of the material strength, and the mechanical strength of the magnetic core such as radial crushing strength can be significantly improved. Further, the oxidation treatment is reduced by the curing treatment in a nitrogen atmosphere, and the reduction of the magnetic characteristics such as the saturation magnetic flux density and the relative permeability is suppressed.
The magnetic core of the present invention can achieve material yield improvement, man-hour reduction, productivity improvement and cost reduction by near net shape by powder metallurgy, and can be preferably used for induction hardening coils.
等速自在継手の外側継手部材は、円柱状の素材から冷間鍛造などの鍛造過程を経て製造され、その後、高周波焼き入れされる。この高周波焼き入れは、外側継手部材のカップ部分の内外面および軸部において高周波焼き入れの焼き入れ度を調整するために、高周波コイルの前面もしくは背面に磁性コアを配置して実施されることが多い。 The outer joint member of the constant velocity universal joint is manufactured from a cylindrical material through a forging process such as cold forging, and then induction-hardened. The induction hardening should be carried out by disposing a magnetic core on the front or back surface of the high frequency coil in order to adjust the degree of hardening of the induction hardening on the inner and outer surfaces and the shaft of the cup portion of the outer joint member. There are many.
磁性コアの一例を図１に示す。図１は磁性コアの斜視図である。磁性コア１は、樹脂被膜が粒子表面に形成された鉄系軟磁性体粉末を圧縮成形し、その後に熱硬化させて製造される。その後に必要に応じて、切削加工、バレル加工および防錆処理などの後処理を行なう。高周波コイルの形状、大きさ、場所等により、配置される磁性コアの形状等も適宜変更できる。図１に示す磁性コア１は、エポキシ樹脂粉末と鉄系軟磁性体粉末との圧縮成形体２がコの字型になっており、このコの字型の凹み部３が高周波コイルの前面もしくは背面に配置される。 An example of the magnetic core is shown in FIG. FIG. 1 is a perspective view of a magnetic core. The magnetic core 1 is manufactured by compression molding an iron-based soft magnetic powder having a resin film formed on the surface of the particles and then heat curing it. After that, post processing such as cutting, barrel processing and rustproofing is performed as needed. The shape or the like of the magnetic core to be disposed can be changed as appropriate depending on the shape, size, location or the like of the high frequency coil. A magnetic core 1 shown in FIG. 1 has a U-shaped compression molded body 2 of an epoxy resin powder and an iron-based soft magnetic powder, and the U-shaped recess 3 is formed on the front surface of the high-frequency coil. It is placed on the back.
本発明に使用できる鉄系軟磁性体粉末としては、純鉄、鉄−シリコン系合金、鉄−窒素系合金、鉄−ニッケル系合金、鉄−炭素系合金、鉄−ホウ素系合金、鉄−コバルト系合金、鉄−リン系合金、鉄−ニッケル−コバルト系合金および鉄−アルミニウム−シリコン系合金（センダスト合金）などの粉末を用いることができる。 Examples of iron-based soft magnetic powders that can be used in the present invention include pure iron, iron-silicon alloys, iron-nitrogen alloys, iron-nickel alloys, iron-carbon alloys, iron-boron alloys, iron-cobalt Powders such as base alloys, iron-phosphorus alloys, iron-nickel-cobalt alloys and iron-aluminum-silicon alloys (sendust alloys) can be used.
上記鉄系軟磁性体粉末の中でも、純鉄が好ましく、特に粉末冶金に用いられている還元鉄粉またはアトマイズ鉄粉が好ましい。より好ましくは得られる磁性コアの機械的特性が優れる還元鉄粉である。還元鉄粉は、製鉄工場で発生する酸化鉄などをコークス等で還元し、次に水素雰囲気で熱処理して製造される鉄粉であり、粒子内に空孔を有している。また、アトマイズ鉄粉は、溶けた鋼を高圧水で粉化・冷却し、その後水素雰囲気で熱処理して製造される鉄粉であり、粒子内に空孔がない。還元鉄粉の断面写真は表面に凹凸が多く見られ、この凹凸が図６に示す圧環強度に影響していると考えられる。 Among the above-mentioned iron-based soft magnetic powders, pure iron is preferable, and in particular, reduced iron powder or atomized iron powder used in powder metallurgy is preferable. More preferably, it is reduced iron powder which is excellent in the mechanical properties of the magnetic core obtained. Reduced iron powder is iron powder produced by reducing iron oxide or the like generated in an iron factory with coke and then heat-treating in a hydrogen atmosphere, and has pores in the particles. Atomized iron powder is iron powder produced by pulverizing and cooling molten steel with high-pressure water and then heat-treating in a hydrogen atmosphere, and there are no pores in the particles. In the cross-sectional photograph of the reduced iron powder, many irregularities are seen on the surface, and this irregularity is considered to affect the radial crushing strength shown in FIG.
これら鉄系軟磁性体粉末は、８０メッシュを通過し、３２５メッシュを通過しない粒子であることが好ましい。８０メッシュは篩目開きが１７７μｍであり、また３２５メッシュは４４μｍである。そのため鉄系軟磁性体粉末の粒子径の範囲は４４μｍ〜１７７μｍである。好ましい範囲は、１００メッシュ（１４９μｍ）を通過し、２５０メッシュ（６３μｍ）を通過しない粒子である。３２５メッシュを通過する微粉は、鉄粒子表面への樹脂被膜の形成が困難になり、８０メッシュ不通過の鉄粉は鉄損が大きくなる。 The iron-based soft magnetic powder is preferably particles which pass through 80 mesh and do not pass through 325 mesh. The 80 mesh has a mesh size of 177 μm and the 325 mesh has a 44 μm. Therefore, the range of the particle diameter of the iron-based soft magnetic powder is 44 μm to 177 μm. A preferred range is particles that pass 100 mesh (149 μm) and do not pass 250 mesh (63 μm). The fine powder passing through the 325 mesh makes it difficult to form a resin film on the surface of the iron particles, and the iron powder non-passing through the 80 mesh has a large iron loss.
還元鉄粉とアトマイズ鉄粉との比較、および還元鉄粉の粒子径による特性比較を検討した結果を図２〜図７に示す。
還元鉄粉として、（１）１００メッシュを通過して３２５メッシュを通過しない鉄粉粒子（以下、還元鉄粉という）と、（２）３２５メッシュを通過する鉄粉粒子（以下、還元鉄粉（微粉）という）と、（３）１００メッシュを通過して３２５メッシュを通過しないアトマイズ鉄粉粒子（以下、アトマイズ鉄粉という）とを準備する。
次に、これら（１）〜（３）の鉄粉９７．３質量％に潜在性硬化剤を含むエポキシ樹脂粉末２．７質量％を配合して、ニーダーを用いて１１０℃で加熱混練後、粉砕して複合磁性粉末を製造した。この複合磁性粉末を金型を用いて４００ＭＰａの成形圧力で圧縮成形し、１８０℃の温度で１時間窒素雰囲気で硬化させて、さらに切削加工を施し、内径７．６ｍｍφ、外径１２．６ｍｍφ、厚さ５．７ｍｍの平円筒状の磁性コアを得た。この磁性コアに一次側巻線および二次側巻線を巻回してトロイダル状の供試試験片を得た。一次側巻線に直流を通電して磁化力（Ａ／ｍ）を変化させたときの二次側巻線の磁束密度を測定して直流Ｂ−Ｈ特性を測定した。結果を図２に示す。
直流Ｂ−Ｈ特性は、還元鉄粉およびアトマイズ鉄粉で同等であり、還元鉄粉（微粉）が低下した。還元鉄粉（微粉）の場合、樹脂被膜が均一に形成し難いため、圧縮成形時の圧縮性に劣り、磁性コアの密度が低くなるためと考えられる。
The result of having examined the comparison with the reduced iron powder and the atomized iron powder, and the characteristic comparison by the particle diameter of reduced iron powder is shown in FIGS.
As reduced iron powder, (1) iron powder particles that pass through 100 mesh and do not pass through 325 mesh (hereinafter referred to as reduced iron powder), and (2) iron powder particles that pass through 325 mesh (hereinafter referred to as reduced iron powder (hereinafter referred to as reduced iron powder) Preparation of atomized iron powder particles (hereinafter referred to as atomized iron powder) called (fine powder) and (3) 100 mesh and not 325 mesh.
Next, 2.7 mass% of epoxy resin powder containing a latent curing agent is mixed with 97.3 mass% of iron powder of (1) to (3), and heat kneading is performed at 110 ° C. using a kneader, It ground and manufactured composite magnetic powder. This composite magnetic powder is compression-molded at a molding pressure of 400 MPa using a mold, cured in a nitrogen atmosphere at a temperature of 180 ° C. for 1 hour, and further subjected to cutting, so that an inner diameter of 7.6 mmφ, an outer diameter of 12.6 mmφ, A flat cylindrical magnetic core of 5.7 mm in thickness was obtained. A primary side winding and a secondary side winding were wound around the magnetic core to obtain a toroidal test specimen. The direct current B-H characteristics were measured by measuring the magnetic flux density of the secondary side winding when passing a direct current through the primary side winding to change the magnetizing force (A / m). The results are shown in FIG.
The direct current B-H characteristics were the same for reduced iron powder and atomized iron powder, and reduced reduced iron powder (fine powder). In the case of reduced iron powder (fine powder), it is difficult to form a resin film uniformly, which is considered to be inferior in compressibility at the time of compression molding and to reduce the density of the magnetic core.
上記還元鉄粉、アトマイズ鉄粉および還元鉄粉（微粉）を用いた磁性コアにそれぞれインダクタンスが１０μＨとなるように巻線の巻回数を調製し、１ｋＨｚにおけるインダクタンスを１００％として、周波数を変化させたときのインダクタンスおよび比透磁率を測定した。結果を図３および図４に示す。
図３に示すインダクタンス変化率は３者とも同等であった。図４に示す比透磁率は、還元鉄粉およびアトマイズ鉄粉は同等であったが、還元鉄粉（微粉）の比透磁率は低下した。これは絶縁被膜が均一に形成していないことや、微粉末のため圧縮性が劣り、密度が低くなったことによると考えられる。
Adjust the number of turns of the magnetic core using the reduced iron powder, atomized iron powder and reduced iron powder (fine powder) so that the inductance is 10 μH, and change the frequency at 1 kHz inductance to 100%. Inductance and relative permeability were measured. The results are shown in FIG. 3 and FIG.
The rate of change in inductance shown in FIG. 3 was equal for all three. The relative permeability shown in FIG. 4 was the same for reduced iron powder and atomized iron powder, but the reduced permeability of reduced iron powder (fine powder) was reduced. This is considered to be due to the fact that the insulating coating is not uniformly formed, or the fine powder has poor compressibility and low density.
上記磁性コアを用いて鉄損を測定した。結果を図５に示す。図５に示すように、鉄損は、還元鉄粉とアトマイズ鉄粉での差はほとんど見られなかった。還元鉄粉（微粉）は僅かに鉄損が大きくなった。鉄粉単体では微粉を使った方が一般的に鉄損（渦電流損）は小さくなるが、図５においては逆転した。この理由は、還元鉄粉（微粉）の場合は樹脂被膜が均一に形成しにくいため、絶縁被膜されていない部分が粒子集合体（見かけ上の粗粉）となって作用したものと考えられる。 The core loss was measured using the above magnetic core. The results are shown in FIG. As shown in FIG. 5, there was almost no difference in iron loss between the reduced iron powder and the atomized iron powder. The iron loss of the reduced iron powder (fine powder) slightly increased. Iron powder (eddy current loss) is generally smaller when iron powder alone is used as fine powder, but it is reversed in FIG. The reason for this is considered that since the resin film is difficult to form uniformly in the case of reduced iron powder (fine powder), the portion not coated with the insulating film acts as a particle aggregate (apparent coarse powder).
上記磁性コアの圧環強度を測定した。測定は、磁性コアに、その直径方向の荷重を破壊が生じるまで連続して加え、破壊したときの荷重を測定した。結果を図６および図７に示す。なお、図７は、圧縮成形後の硬化条件を１８０℃の温度で１時間窒素雰囲気で硬化させた場合と、同温度および時間にて空気雰囲気で硬化させた場合との比較を表している。
図６に示すように、還元鉄粉を用いた磁性コアがアトマイズ鉄粉を用いた磁性コアよりも１０％程度圧環強度が高くなる。還元鉄粉の方がアトマイズ鉄粉よりも粉末同士の絡みが生じるためと考えられる。還元鉄粉（微粉）の磁性コアが最も圧環強度が低かった。これは、樹脂被膜が均一に形成しにくいため、鉄素地が接触する頻度が高まり、鉄粉同士が接着されてない箇所が多く存在するためと考えられる。
図７に示すように、窒素雰囲気で硬化させた磁性コアの圧環強度が優れていた。これは一部露出している鉄粉表面の酸化が抑えられるためと考えられる。
The radial crushing strength of the magnetic core was measured. In the measurement, the load in the diametrical direction was continuously applied to the magnetic core until failure occurred, and the load at the time of failure was measured. The results are shown in FIG. 6 and FIG. FIG. 7 shows a comparison of the curing conditions after compression molding in a nitrogen atmosphere at a temperature of 180 ° C. for 1 hour and in the air atmosphere at the same temperature and time.
As shown in FIG. 6, the crushing strength of the magnetic core using reduced iron powder is about 10% higher than that of the magnetic core using atomized iron powder. It is considered that reduced iron powder causes entanglement between powders than atomized iron powder. The magnetic core of the reduced iron powder (fine powder) had the lowest radial crushing strength. It is considered that this is because the resin coating is difficult to form uniformly, the frequency of contact with the iron base increases, and there are many places where the iron powders are not adhered to each other.
As shown in FIG. 7, the radial crushing strength of the magnetic core cured in a nitrogen atmosphere was excellent. It is considered that this is because the oxidation of the partially exposed iron powder surface is suppressed.
以上の結果、本願発明に好ましく使用できる鉄粉としては、８０メッシュの篩を通過し、３２５メッシュの篩を通過しない還元鉄粉である分かった。 As a result, it was found that the iron powder that can be preferably used in the present invention is reduced iron powder that passes through an 80-mesh sieve and does not pass through a 325-mesh sieve.
本発明に使用できるエポキシ樹脂は、接着用エポキシ樹脂として使用できる樹脂であって軟化温度が１００〜１２０℃の樹脂が好ましい。例えば、室温では固体であるが、５０〜６０℃でペースト状になり、１３０〜１４０℃で流動性になり、さらに加熱を続けると硬化反応が始まるエポキシ樹脂であれば使用できる。この硬化反応は１２０℃付近でも始まるが、実用的な硬化時間、例えば２時間以内で硬化反応が終了する温度としては１７０〜１９０℃であることが好ましい。この温度範囲であると、硬化時間は４５〜８０分である。 The epoxy resin that can be used in the present invention is a resin that can be used as an adhesive epoxy resin, and a resin having a softening temperature of 100 to 120 ° C. is preferable. For example, an epoxy resin that is solid at room temperature, becomes a paste at 50 to 60 ° C., becomes fluid at 130 to 140 ° C., and starts a curing reaction when further heated can be used. This curing reaction starts at around 120 ° C., but the temperature at which the curing reaction is completed within a practical curing time, for example, 2 hours, is preferably 170 to 190 ° C. In this temperature range, the curing time is 45-80 minutes.
エポキシ樹脂の樹脂成分としては、例えばビスフェノールＡ型エポキシ樹脂、ビスフェノールＦ型エポキシ樹脂、ビスフェノールＳ型エポキシ樹脂、水添ビスフェノールＡ型エポキシ樹脂、水添ビスフェノールＦ型エポキシ樹脂、スチルベン型エポキシ樹脂、トリアジン骨格含有エポキシ樹脂、フルオレン骨格含有エポキシ樹脂、脂環式エポキシ樹脂、ノボラック型エポキシ樹脂、アクリルエポキシ樹脂、グリシジルアミン型エポキシ樹脂、トリフェノールフェノールメタン型エポキシ樹脂、アルキル変性トリフェノールメタン型エポキシ樹脂、ビフェニル型エポキシ樹脂、ジシクロペンタジエン骨格含有エポキシ樹脂、ナフタレン骨格含有エポキシ樹脂、アリールアルキレン型エポキシ樹脂等が挙げられる。 As a resin component of the epoxy resin, for example, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, hydrogenated bisphenol A epoxy resin, hydrogenated bisphenol F epoxy resin, stilbene epoxy resin, triazine skeleton -Containing epoxy resin, fluorene skeleton-containing epoxy resin, alicyclic epoxy resin, novolak epoxy resin, acrylic epoxy resin, glycidyl amine epoxy resin, triphenolphenolmethane epoxy resin, alkyl-modified triphenolmethane epoxy resin, biphenyl epoxy resin Epoxy resin, dicyclopentadiene skeleton-containing epoxy resin, naphthalene skeleton-containing epoxy resin, aryl alkylene type epoxy resin and the like can be mentioned.
エポキシ樹脂の硬化剤成分は潜在性エポキシ硬化剤である。潜在性エポキシ硬化剤を用いることにより、軟化温度を１００〜１２０℃に、また硬化温度を１７０〜１９０℃に設定することができ、鉄粉粉末への絶縁性塗膜の形成と、その後の圧縮成形および熱硬化を行なうことができる。
潜在性エポキシ硬化剤としては、ジシアンジアミド、三フッ化ホウ素−アミン錯体、有機酸ヒドラジド等が挙げられる。これらの中で、上記硬化条件に適合するジシアンジアミドが好ましい。
また、潜在性エポキシ硬化剤と共に、三級アミン、イミダゾール、芳香族アミンなどの硬化促進剤を含むことができる。
The hardener component of the epoxy resin is a latent epoxy hardener. By using a latent epoxy curing agent, the softening temperature can be set to 100 to 120 ° C., and the curing temperature can be set to 170 to 190 ° C., to form an insulating coating film on iron powder, and thereafter compression. It can be molded and heat cured.
Examples of the latent epoxy curing agent include dicyandiamide, boron trifluoride-amine complex, and organic acid hydrazide. Among these, dicyandiamide compatible with the above-mentioned curing conditions is preferred.
In addition to the latent epoxy curing agent, curing accelerators such as tertiary amines, imidazoles and aromatic amines can be included.
本発明で使用できる上記潜在性硬化剤を含むエポキシ樹脂は、１６０℃で２時間、１７０℃で８０分、１８０℃で５５分、１９０℃で４５分、２００℃で３０分の硬化条件となるように潜在性硬化剤を配合する。 The epoxy resin containing the latent curing agent that can be used in the present invention has curing conditions of 160 ° C. for 2 hours, 170 ° C. for 80 minutes, 180 ° C. for 55 minutes, 190 ° C. for 45 minutes, and 200 ° C. for 30 minutes. Mix the latent hardener as you like.
鉄系軟磁性体粉末とエポキシ樹脂の配合割合は、これらの合計量に対して、鉄系軟磁性体粉末が９５〜９９質量％、潜在性硬化剤を含むエポキシ樹脂が１〜５質量％である。エポキシ樹脂が１質量％未満であると、絶縁被膜の形成が困難であり、５質量％を超えると磁気特性の低下と樹脂リッチな粗大な凝集体が発生するからである。 The blending ratio of the iron-based soft magnetic powder and the epoxy resin is 95 to 99% by mass of the iron-based soft magnetic powder and 1 to 5% by mass of the epoxy resin containing the latent curing agent with respect to the total amount. is there. This is because if the epoxy resin is less than 1% by mass, it is difficult to form an insulating coating, and if it exceeds 5% by mass, the magnetic properties are degraded and a resin-rich coarse aggregate is generated.
本発明の磁性コアは、上記鉄系軟磁性体粉末と、上記エポキシ樹脂とを１００〜１２０℃の温度で乾式混合することで、鉄系軟磁性体粉末表面に未硬化樹脂被膜を形成する。この未硬化樹脂被膜は絶縁被膜であり、熱硬化後も絶縁被膜である。被膜の絶縁性が維持されるので、磁気コアとしての磁気特性が向上する。
絶縁被膜が表面に形成された鉄系軟磁性体粉末は、金型を用いる圧縮成形により成形体となし、その後エポキシ樹脂の熱硬化開始温度以上の温度で熱硬化させることで一体化された磁性コアが得られる。
The magnetic core of the present invention forms an uncured resin coating on the surface of the iron-based soft magnetic powder by dry-mixing the iron-based soft magnetic powder and the epoxy resin at a temperature of 100 to 120 ° C. This uncured resin film is an insulating film and is an insulating film even after heat curing. Since the insulating property of the film is maintained, the magnetic properties as a magnetic core are improved.
An iron-based soft magnetic powder with an insulating coating formed on its surface is formed into a compact by compression molding using a mold, and then heat-cured at a temperature equal to or higher than the thermal curing start temperature of the epoxy resin. A core is obtained.
本発明の磁性コアは、磁気特性および圧環強度などの機械的特性に優れている。また、成形したのち切削加工性に優れている。このため、薄型の磁性コア、特殊形状の磁性コアを容易に製造できる。そのため、等速自在継手の外側継手部材等に利用できる。 The magnetic core of the present invention is excellent in mechanical properties such as magnetic properties and radial crushing strength. Moreover, it is excellent in machinability after molding. Therefore, a thin magnetic core and a specially shaped magnetic core can be easily manufactured. Therefore, it can utilize for the outer joint member etc. of a constant velocity universal joint.
上記磁性コアの製造方法を図８により説明する。図８は製造工程図である。
上述した鉄系軟磁性体粉末と、上述した潜在性硬化剤が既に配合されているエポキシ樹脂とをそれぞれ準備する。鉄系軟磁性体粉末は予め分級機により８０メッシュの篩を通過し、３２５メッシュの篩を通過しない粒子に調整されている。
混合工程により、鉄系軟磁性体粉末とエポキシ樹脂とを該エポキシ樹脂の軟化温度以上、熱硬化開始温度未満の温度で乾式混合する。この混合工程においては、最初に鉄系軟磁性体粉末とエポキシ樹脂とを室温で十分にブレンダー等を用いて混合する。次に、混合された混合物をニーダー等の混合機に投入してエポキシ樹脂の軟化温度（１００〜１２０℃）にて加熱混合する。この加熱混合の工程により、鉄系軟磁性体粉末の表面にエポキシ樹脂の絶縁被膜が形成される。この段階ではエポキシ樹脂は未硬化である。
The method of manufacturing the magnetic core will be described with reference to FIG. FIG. 8 is a manufacturing process diagram.
The above-described iron-based soft magnetic powder and an epoxy resin in which the above-described latent curing agent is already blended are prepared. The iron-based soft magnetic powder is previously adjusted by a classifier to particles that pass through an 80-mesh sieve and do not pass through a 325-mesh sieve.
In the mixing step, the iron-based soft magnetic powder and the epoxy resin are dry-mixed at a temperature higher than the softening temperature of the epoxy resin and lower than the heat curing start temperature. In this mixing step, first, the iron-based soft magnetic powder and the epoxy resin are mixed sufficiently at room temperature using a blender or the like. Next, the mixed mixture is put into a mixer such as a kneader and heated and mixed at the softening temperature (100 to 120 ° C.) of the epoxy resin. By the heating and mixing process, an insulating coating of epoxy resin is formed on the surface of the iron-based soft magnetic powder. At this stage, the epoxy resin is uncured.
ニーダー等の混合機を用いて加熱混合された内容物は、凝集したケーキ状となっている。粉砕工程は、この凝集ケーキを室温で粉砕して篩分けすることにより、表面にエポキシ樹脂の絶縁膜が形成された複合磁性粉末を得る工程である。粉砕はヘンシェルミキサーが好ましく、篩分けは６０メッシュ通過分の粒度とすることが好ましい。 The contents heated and mixed using a mixer such as a kneader are in the form of an agglomerated cake. The pulverization step is a step of obtaining a composite magnetic powder having an epoxy resin insulating film formed on the surface thereof by pulverizing and sieving the agglomerated cake at room temperature. It is preferable to grind | pulverize a Henschel mixer and to sieve it as the particle size of 60 mesh passage.
圧縮成形工程において使用される金型は２００〜５００ＭＰａの成形圧力を印加できる金型であればよい。成形圧力が２００ＭＰａ未満では磁気特性や強度が低く、５００ＭＰａを超えるとエポキシ樹脂が金型内壁に固着するからである。 The mold used in the compression molding process may be a mold to which a molding pressure of 200 to 500 MPa can be applied. When the molding pressure is less than 200 MPa, the magnetic properties and the strength are low, and when it exceeds 500 MPa, the epoxy resin adheres to the inner wall of the mold.
金型より取り出された成形品は、１７０〜１９０℃の温度で、４５〜８０分加熱硬化される。１７０℃未満では硬化に長時間かかり、１９０℃を超えると劣化が始まるからである。加熱硬化は、窒素雰囲気で行なうことが好ましい。
加熱硬化後、必要に応じて、切削加工、バレル加工、防錆処理などを行ない磁性コアが得られる。
The molded product removed from the mold is heat cured at a temperature of 170 to 190 ° C. for 45 to 80 minutes. If it is less than 170 ° C., curing takes a long time, and if it exceeds 190 ° C., deterioration starts. The heat curing is preferably performed in a nitrogen atmosphere.
After heat curing, cutting, barreling, rustproofing, etc. are performed as necessary to obtain a magnetic core.
実施例１、比較例１および比較例２
１００メッシュを通過して２５０メッシュを通過しない鉄粉粒子９７．３ｇと、硬化剤としてジシアンジアミドを含むエポキシ樹脂粉末２．７ｇとをブレンダーにて室温で１０分間混合した。この混合物をニーダーに投入して１１０℃で１５分間加熱混練した。ニーダーより凝集したケーキを取り出して冷却した後、粉砕機で粉砕した。次いで金型を用いて４００ＭＰａの成形圧力で圧縮成形した。圧縮成形品を金型より取り出し、１８０℃の温度で１時間窒素雰囲気で硬化させた。さらに切削加工を施し磁性コアを製造した。
また、上述した磁気特性測定用トロイダル状の試験片を作製し、磁気特性を上述した方法で測定した。また、表面硬さ、体積抵抗、表面抵抗測定用として１０ｍｍ×２５ｍｍ×３ｍｍ厚さの試験片を作製した。測定結果を表１に示す。
なお、鉄粉をポリテトラフルオロエチレンで固着した磁性コア（比較例１）、センダスト粉をフェノール樹脂で固着した磁性コア（比較例２）を上記試験片と同一の形状として、実施例１と同一の評価を行なった。切削加工の工程で、比較例１および比較例２の磁性コアは機械的強度が弱く、薄肉部の切削可能では割れ、クラックが発生した。結果を表１に示す。
Example 1, Comparative Example 1 and Comparative Example 2
97.3 g of iron powder particles passing 100 mesh and not 250 mesh and 2.7 g of epoxy resin powder containing dicyandiamide as a curing agent were mixed in a blender for 10 minutes at room temperature. The mixture was charged into a kneader and heat-kneaded at 110 ° C. for 15 minutes. The coagulated cake was taken out of the kneader, cooled, and then ground with a grinder. Next, it was compression molded at a molding pressure of 400 MPa using a mold. The compression molded product was removed from the mold and cured at a temperature of 180 ° C. for 1 hour in a nitrogen atmosphere. Further, cutting was performed to produce a magnetic core.
Moreover, the toroidal test piece for magnetic characteristic measurement mentioned above was produced, and the magnetic characteristic was measured by the method mentioned above. Moreover, the test piece of 10 mm x 25 mmx3 mm thickness was produced for surface hardness, volume resistance, and surface resistance measurement. The measurement results are shown in Table 1.
In addition, the magnetic core (Comparative Example 1) in which iron powder is fixed with polytetrafluoroethylene and the magnetic core (Comparative Example 2) in which Sendust powder is fixed with phenol resin are formed in the same shape as the above test piece, and is the same as in Example 1. Was evaluated. In the cutting process, the magnetic cores of Comparative Example 1 and Comparative Example 2 had low mechanical strength, and cracks and cracks occurred when the thin part was cut. The results are shown in Table 1.
本発明の磁性コアは、経済性、磁気特性および材料強度に優れているので、汎用の磁性コアとして利用できる。また、複雑な形状を必要とされる、例えば高周波焼入装置の加熱コイル部に取り付けられる軟質磁性コアとして利用できる。 Since the magnetic core of the present invention is excellent in economy, magnetic properties and material strength, it can be used as a general-purpose magnetic core. In addition, it can be used as a soft magnetic core that is required to have a complicated shape, for example, attached to the heating coil portion of the induction hardening apparatus.
１ 磁性コア
２ 圧縮成形体
３ 凹み部
1 magnetic core 2 compression molded body 3 recessed portion
Claims (4)
接着用樹脂としてエポキシ樹脂が用いられ、
硬化反応が終了した前記エポキシ樹脂による絶縁被膜を表面に有する前記鉄系軟磁性体粉末が該絶縁被膜を介して一体化された圧縮成形体であり、
前記エポキシ樹脂が潜在性硬化剤を含むエポキシ樹脂であり、前記潜在性硬化剤がジシアンジアミドであり、この潜在性硬化剤を含むエポキシ樹脂の軟化温度が１００〜１２０℃であることを特徴とする磁性コア。 As the iron-based soft magnetic powder, an iron-based soft magnetic powder of a particle that passes through 100 mesh with a Tyler sieve number and does not pass through the same 325 mesh is used.
Epoxy resin is used as the adhesive resin,
Compacts der that the iron-based soft magnetic powder is integrated through the insulating film having a dielectric coating according to the epoxy resin curing reaction is completed to the surface is,
The epoxy resin is an epoxy resin containing a latent curing agent, the latent curing agent is dicyandiamide, and the softening temperature of the epoxy resin containing the latent curing agent is 100 to 120 ° C. core.
接着用樹脂としてエポキシ樹脂が用いられ、
硬化反応が終了した前記エポキシ樹脂による絶縁被膜を表面に有する前記鉄系軟磁性体粉末が該絶縁被膜を介して一体化された圧縮成形体であり、
前記磁性コアが高周波焼入コイルに使用される磁性コアであることを特徴とする磁性コア。 As the iron-based soft magnetic powder, an iron-based soft magnetic powder of a particle that passes through 100 mesh with a Tyler sieve number and does not pass through the same 325 mesh is used.
Epoxy resin is used as the adhesive resin,
Compacts der that the iron-based soft magnetic powder is integrated through the insulating film having a dielectric coating according to the epoxy resin curing reaction is completed to the surface is,
A magnetic core characterized in that the magnetic core is a magnetic core used for an induction hardening coil .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018187447A JP6554221B2 (en) | 2018-10-02 | 2018-10-02 | Magnetic core |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018187447A JP6554221B2 (en) | 2018-10-02 | 2018-10-02 | Magnetic core |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2017057083A Division JP6415621B2 (en) | 2017-03-23 | 2017-03-23 | Magnetic core |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| JP2019016806A JP2019016806A (en) | 2019-01-31 |
| JP2019016806A5 JP2019016806A5 (en) | 2019-03-14 |
| JP6554221B2 true JP6554221B2 (en) | 2019-07-31 |
Family
ID=65356592
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2018187447A Active JP6554221B2 (en) | 2018-10-02 | 2018-10-02 | Magnetic core |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6554221B2 (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0480901A (en) * | 1990-07-24 | 1992-03-13 | Tdk Corp | Bonded magnet and manufacture thereof |
| JPH09223618A (en) * | 1996-02-16 | 1997-08-26 | Hitachi Metals Ltd | Bonded soft magnetic substance for speaker magnetic circuit |
| JP2003124035A (en) * | 2001-10-15 | 2003-04-25 | Daido Steel Co Ltd | Core material |
| JP2003189560A (en) * | 2001-12-19 | 2003-07-04 | Matsushita Electric Ind Co Ltd | Method for manufacturing core built-in type magnet rotor and permanent magnet type motor |
| JP4723442B2 (en) * | 2006-09-11 | 2011-07-13 | 株式会社神戸製鋼所 | Powder cores and iron-based powders for dust cores |
| JP5090095B2 (en) * | 2007-07-24 | 2012-12-05 | 新日鐵化学株式会社 | Epoxy resin composition |
| WO2011126120A1 (en) * | 2010-04-09 | 2011-10-13 | 日立化成工業株式会社 | Coated metal powder, dust core and method for producing same |
-
2018
- 2018-10-02 JP JP2018187447A patent/JP6554221B2/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| JP2019016806A (en) | 2019-01-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6580817B2 (en) | Manufacturing method of magnetic core | |
| KR100545849B1 (en) | Manufacturing method of iron-based amorphous metal powder and manufacturing method of soft magnetic core using same | |
| JP5924480B2 (en) | Magnetic powder material, low-loss composite magnetic material including the magnetic powder material, and magnetic element including the low-loss composite magnetic material | |
| JP6427862B2 (en) | Dust core, manufacturing method thereof, inductance element using the dust core, and rotating electric machine | |
| KR101717064B1 (en) | Soft magnetic metal powder-compact magnetic core and reactor | |
| JP6117504B2 (en) | Manufacturing method of magnetic core | |
| US9245676B2 (en) | Soft magnetic alloy powder, compact, powder magnetic core, and magnetic element | |
| WO2018179812A1 (en) | Dust core | |
| JP2009044068A (en) | Coil component | |
| JP6519418B2 (en) | Soft magnetic metal dust core | |
| JP2017188680A (en) | Magnetic material, magnetic core, and method for manufacturing the same | |
| JP4325793B2 (en) | Manufacturing method of dust core | |
| JP6554221B2 (en) | Magnetic core | |
| JP6581270B2 (en) | Manufacturing method of magnetic core | |
| JP6415621B2 (en) | Magnetic core | |
| JP2006100292A (en) | Dust core manufacturing method and dust core manufactured thereby | |
| WO2022070789A1 (en) | Magnetic core material and magnetic core | |
| JP2022058148A (en) | Magnetic core material and magnetic core | |
| JPH11329821A (en) | Dust core and manufacture thereof | |
| WO2022070786A1 (en) | Dust core | |
| JP2019029676A (en) | Amorphous magnetic core and magnetic device | |
| JPH1197228A (en) | Dust core and its manufacture | |
| JP2019029675A (en) | Amorphous magnetic core and magnetic device | |
| JP2000049009A (en) | Dust core and its manufacture |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20181031 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20190204 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20190219 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20190416 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20190611 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20190705 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6554221 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |